“Markets cannot escape the gravitational pull of the Fed, so the stocks are under pressure because of the fact that we may see interest rates rise in December,” Kim Forrest, senior analyst and portfolio manager at Fort Pitt Capital Group, told MarketWatch.

The market ran up pretty hard the past six weeks, giving the U.S. equity market the most technical strength it has seen since at least the August selloff, Instinet Executive Director Frank Cappelleri told The Wall Street Journal.

But if the market rolls over with this much buying momentum behind it, there isn’t much to arrest the slide. “The run is certainly getting to a point where the biggest gains may be behind us – at least for the short-term,” he said.

“And if the Fed does raise, it will kick the stock market into low gear or take it down a lot, and it will also slow the economy and put it into recession, next year being an election year," he predicted to CNBC.

"We'll start next year with lower stock prices and a slower economy,” he said.